Sound reproducing system



Sept. 23, 1958 s. D. NOBLE SOUND REPRODUCING SYSTEM Filed March 29, 1954 w IIIIIIIIAI VIIIIIIIIIJ I}; &

STUART D NOBLE INVENTOR.

Huebner Beeh/er,

Worre/ 8 Herz/g.

Aflarneys.

United States Patent 2,853,561 SOUND REPRODUCING SYSTEM Stuart D. Noble, Hollywood, Calif. Application March 29, 1954, Serial No. 419,140 Claims. (Cl. 179-1004) The invention relates to the mechanical phase of sound reproduction in devices or units wherein it is desirable to play back the impression made upon some medium by a sound recording apparatus.

More particularly the invention has reference to employment of vibratory motion generated in a sound recording head for the purpose of activating the diaphragm of a loud-speaker, thereby to produce sound.

During recent years considerable attention has been given to the perfecting of sound reproducing systems to achieve high fidelity and accuracy in reproduction. Loud-speaker units have been developed to a considerable degree and so connected into sound circuits as to be electrically activated. In pursuing a course directed to the improved reproduction of desirable frequencies in the pattern of the most usual sounds, apparatus has tended to become precision apparatus involving a corresponding high cost. With these systems currently manufactured to meet the demands suggested, an unnecessarily complex structure is usually employed and often one wherein assemblies are heavy and occupy a substantial amount of space, all of which has a considerable effect on their lack of acceptability for many uses and purposes.

It is therefore among the objects of the invention to provide a new and improved sound reproducing system which is particularly low in cost by reason of employment of certain portions of the device, namely, the sound recording head, to perform a double function, namely, that of actuating a loud-speaker.

' Another object of the invention is to. provide a new and improved sound reproducing system wherein mechanical vibrations set up in a sound recording head normally for the purpose of making an impression upon some carrier such as a tape or disk can be alternatively utilized to produce audible sound through the agency of a loud-speaker.

-Still another object of the invention is to provide a new and improved sound reproducing system which, because -of the double functioning of certainof its parts, makes possible the production of a combined recording and-reproducing unit in a particularly small package.

Still further among the objects of the invention is to .provide a new and improved sound reproducing system which is positive and direct inthe application of mechanical vibratory frequencies to a loud-speaker and still sufiiciently simple thatit can be adapted to a great many different types of sound impression carriers and electronic reproducing systems without the necessity of .designing special means to adapt the system to a great variety of sound reproducing and recording mediums presently available.

With these and other objects in view, .the invention consists in the construction, arrangement and combination of the various parts of the device whereby the objects contemplated are attained, as hereinafter set forth, pointed out in the appended claims and illustrated in the accompanying drawings. 3 a

In the drawings;

Figure l is a front elevational view showing relative locations of a sound recording head and a loud-speaker stances.

ice

2 Figure 2 is a sectional view taken on the line 2-2 of Figure 1. I

Figure 3 is an end view partially 1n section on the line 3-3 of Figure 1.

Figure 4 is a schematic representation of a unit illustrating the combination of the sound recording head and loud-speaker with a sound reproducing head. I

In the embodiment chosen for the purpose of illustration there is shown a portion of a unit casing comprising a wall 10 in which is mounted a loud-speaker 11. As typical of one application of the invention here involved, there is shown an impression carrier 12, here illustrated as a tape, this being presumed to be carried by some conventional means not shown associated with the unit.

A sound recording head 13 is pivotally mounted so as to be shiftable to a first position in sound recording relation to the carrier 12 and a second position removed therefrom as suggested in Figure 4. A sound reproducing head 14 is also pivotally mounted so that it can be moved to a position to follow any impression which may be made upon the carrier 12. An electronic unit 15 is interconnected between the sound reproducing head 14 and sound recording head 13 and also a microphone unit 16. Suitable switches may be provided for disconnecting any selected part of the system.

The loud-speaker member 11 may be inexpensively fabricated from paper, that here shown comprising a cone 17 secured at its rim 18 to the wall 10 so as to cover a circular aperture 19. Some suitable grill 20 may be provided to cover the aperture and protect the cone.

The sound recording head is here shown pivotally secured to the wall 10 by means of a suitable pivot pin 21 so that the sound recording head is free to tilt between the solid line position of Figure 1 and a dotted line position 13 in the same Figure l.

The sound recording head is shown provided with a stylus 22 adapted to be pressed into impression-making contact with the carrier 12 when the unit is being used as a sound recorder. When in this position of adjustment, audio-frequency vibrations will be induced in the sound recording head 13 by means of the electronic unit 15 activated by sounds caught by the microphone 16. The vibratory effect of the sounds will be traced upon the carrier 12 in order to be saved for future reproduction.

When reproduction is desired, the sound reproducing head 14 will be lowered so that a suitable stylus 23 thereadapted to be connected thereto under certain circumon is in a position to pick up vibrations impressed in the carrier 12 if it be, for example, a tape in which the vibration is impressed either by cutting or indentations, or other acceptable means.

The impressions on the tape 12 thus picked up through the sound reproducing head are converted by suitable action in the electronic unit to create corresponding vibrations in the sound recording head 13. Thus the sound recording head will vibrate as it vibrated initially but will be caused to vibrate through the agency of the sound reproducing head in the last described instance rather than sound vibrations caught and transmitted by the microphone 16.

, ,When it is desired to create audible reproductions of the sound picked up by the sound reproducing head, the sound recording head is raised so that it occupies the solid line position of Figures 1, 2 and 3, this being also the position indicated in the schematic view of Figure 4. It will be noted that a finger 24 is mounted at one end upon the stylus 22 and extends laterally to a position clear of thesound recording head 13 and thence upwardly.

A loud-speaker actuating arm 25 is pivotally mounted 'uponja bracket 126 which in turn is carried by the wall 10. One end 27 of the actuating arm lies in contact with a button 28 at the center or apex of the loud-speaker cone 17. At its other end the actuating arm has a bent portion 29 extending through an aperture 30 in the wall so that an outer end 31 of the actuating arm lies in a position of potential engagement with the finger 24. A pad 32 of suitable damping material may be provided at the outermost end so as to absorb unwanted frequencies of vibrations when the parts herein defined are brought into face to face engagement.

It will be noted that there is resiliency between the sound recording head 13 and the diaphragm which may be supplied either by the flexibility of the diaphragm cone 17 itself, flexibility of the actuating arm 25, or perhaps a slight flexibility in the finger 24. This is necessary so that when the sound recording head 13 is lifted from the dotted position 13' to the solid line position 13 of Figures l, 2 and 3, a bent end 33 of the finger 24 will strike against the outer end 31 of the actuating arm with a dampened blow as the adjacent portion of the finger 24 rides up along the outer end to the solid line position shown. In that position there is a snug face to face contact sufficient so that the actuating arm will follow and remain in contact with the finger throughout the entire range of vibrations created in the sound recording head 13. In the solid line position when the sound reproducing head 14, for example, is made to follow and receive the impressions on the tape 12, those impressions will be carried into the electronic unit and there converted so as to create or impart corresponding vibrations in the sound recording head 13 which will transfer them directly and mechanically to the loud-speaker cone, thereby to generate sound waves in the air corresponding to those picked up by the sound reproducing head.

There has accordingly been herein disclosed and described a particularly simple and effective means of employing the sound recording head as a medium and device for actuating a loud-speaker diaphragm to produce playback from the carrier initially made use of by the sound recording head in preparing the initial record of any sounds sought to be preserved. Although it may not be possible to reproduce the complete band of all frequencies which exist in sound, nevertheless the system herein disclosed and described is accurate and dependable in the reproducing of speech sounds and reproduces musical sounds adequately. The sound quality is one substantially equivalent to that produced by small portable radio sets.

While I have herein shown and described my invention in what I have conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope of my invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a combined vibration recording and reproducing mechanism comprising a loud speaker including a vibrating diaphragm element, the combination of an actuator arm connected at one end to the diaphragm element to activate said diaphragm element at audible vibration frequencies, a movable vibration impression carrier mounted in said mechanism, a recording head movably mounted in said mechanism having a first position free from engagement with said arm and adapted for recording vibrations mechanically on said carrier and having a second position freed from the first position and moved to a location wherein said recording head has a mechanical engagement with said arm and at a location on said arm remote from the diaphragm element whereby vibrations generated in said recording head are transmitted directly to said diaphragm element.

2. In a combined sound recording and reproducing mechanism comprising a support and a loud-speaker diaphragm on the support, the combination of an actuator arm tiltably mounted on the support and having one end connected to the diaphragm to activate said diaphragm at sound frequencies, a sound vibration impression carrier movably mounted on said support, an electrically responsive recording head tiltably mounted on the support having a first position in engagement with said carrier adapted for recording vibrations mechanically on said carrier'and having a second position removed from the first position to a location wherein said recording head has a resilient damped mechanical contact with a portion of said arm remote from the diaphragm whereby vibrations generated in said recording head of a type for recording on said carrier are transmitted to said diaphragm for directly generating audible sound waves.

3. A .sound reproducing unit comprising a support, a sound track carrier movably mounted on said support, a sound recording head on said support including a sound track impressing stylus, said head being mounted for movement to a first position wherein the stylus engages the carrier and a second position wherein the stylus is removed from engagement with the carrier, a sound projecting diaphragm mounted on said support including an actuating arm therefor movably mounted on the support and having a portion in operating engagement with the diaphragm and another portion extending to a location adjacent said recording head, said head comprising a vibrating portion having a position of contact with said other portion of said actuating arm when said recording head is in said second position.

4-. A sound reproducing unit comprising a support, a sound track carrier movably mounted on said support, a sound recording head tiltably mounted on said support including a sound impressing stylus, said head and stylus being mounted for movement to a first position wherein the stylus engages the carrier and a second position wherein the stylus is removed from engagement with the carrier, a loud speaker diaphragm mounted on said support, an actuating arm tiltably mounted on the support and having one end in contact with the center of the diaphragm and another end extending to a location adjacent said recording head, said recording head including a vibrating portion having a position of contact with said other end of said actuating arm when said recording head is in said second position and being free of contact when therecording head is in said first position.

5. An electronic sound reproducing mechanism comprising a support, a sound track carrier movably mounted on said support, an electroresponsive sound recording head tiltably mounted on said support including a sound track forming stylus mounted for movement to a first position wherein. the stylus engages the carrier and a second position wherein the stylus is elevated from engagement with the carrier, an electroresponsive sound playing head on said support including vibration pick up means mounted to receive impressions from said carrier, an electronic unit in said mechanism having connections respectively for both saidheads and a connection adapted to be connected to a-rnicrophone, a loud-speaker diaphragm unit mounted on said support including an actuating arm therefor movably mounted on the support for movement in a direction axially with respect to the diaphragm unit and having an actuator portion extending to a location adjacent said recording head, said recording head including vibrating means having a position of resilient mechanical contact with the actuator portion of said actuating arm when said recording head is in-said second position.

References Cited in the file of this patent UNITED STATES PATENTS 1,596,045 Kaehni et al Aug. 17, 1926 1,597,647 Zitzerman Aug. 24, 1926 1,611,571 Walker Dec. 21, 1926 1,665,740 Jeffries Apr. 10, 1928 

